![U.S. patent history reviewed at a touring model exhibition(4/6)](http://www.ecns.cn/hd/2018/05/15/8ed17a7210f94a99a12534be30de822a.jpg)
The Spirit of Invention brings models designed and made by 19th-century inventors who attempted to bring changes to every aspect of life, from a sewing machine, a wool scissoring machine, a printer to an engine. (Photo/China Daily)
The Spirit of Invention brings models designed and made by 19th-century inventors who attempted to bring changes to every aspect of life, from a sewing machine, a wool scissoring machine, a printer to an engine. (Photo/China Daily)